15
P
Phosphorus
30.9737619985
Phosphorus
POLYATOMIC NONMETAL
Bohr Model: Electrons arranged in energy shells around the nucleus.
Phosphorus is a chemical element with symbol P and atomic number 15. As an element, phosphorus exists in two major forms—white phosphorus and red phosphorus—but due to its high reactivity, phosphorus is never found as a free element on Earth. Instead phosphorus-containing minerals are almost always present in their maximally oxidised state, as inorganic phosphate rocks.
Quick Facts
Atomic Number 15
Period 3
Group 15
Phase Solid
Appearance colourless, waxy white, yellow, scarlet, red, violet, black
About Polyatomic Nonmetals
Polyatomic nonmetals are elements that form bonds with distinct molecular structures. They are generally poor conductors of heat and electricity.
History
Discovered By Hennig Brand
Named By Unknown
Physical Properties
Atomic Mass 30.9737619985
Density 1.823 g/L
Molar Heat 23.824 J/(mol·K)
Phase Transition (Melting & Boiling Points)
Phosphorus phase transition data is unavailable.
Atomic Properties
Electron Config [Ne] 3s2 3p3
Electronegativity 2.19
Electron Affinity 72.037 kJ/mol
Ionization Energy 1011.8 kJ/mol
Orbital Filling Diagram
This diagram visualizes electron configuration according to the Aufbau principle and Hund's rule.
Boxes represent orbitals (s, p, d, f), while arrows indicate electrons with spin up or down.
Electrons fill lower energy levels first and occupy orbitals singly before pairing.
Photograph
Source: Wikipedia
External Resources
Study Guide
Atomic Number
The number of protons in the nucleus, which defines the element.
Atomic Mass
The average mass of an atom, including protons and neutrons.
Electronegativity
A measure of how strongly an atom attracts electrons in a bond.
Ionization Energy
The energy required to remove an electron from an atom.
Electron Config
The arrangement of electrons in the atom's energy shells.